Generic Design Methodology for Electro-Hydraulic Servo Actuator in Aero-Engine Main Fuel Control System Available to Purchase

Focusing on the problem that the high stable quality and excellent servo performance of electrohydraulic actuator are needed in aero-engine control system, this paper aims to propose a complete design method for electrohydraulic servo actuator. Firstly, the static characteristics of mechanical-hydraulic system including solenoid control valve, slave valve and metering valve was analyzed to identify their main structure parameters. Secondly, a nonlinear model of this open-loop mechanical-hydraulic system was established in the framework of AMESim. Thirdly, the model’s transfer function was obtained through Prediction Error Methods (PEM) in system identification. Based on the above work, given that the saturation of duty ratio is a nonlinear link, an integral-separated PI controller was applied to constitute the closed-loop electrohydraulic servo actuator. Moreover, to get optimal performance, the controller parameters design was transferred into an optimization process using Differential Evolution (DE) algorithm. Simulation results illustrated that the designed closed-loop electrohydraulic servo actuator shows rapid servo tracking performance, small overshoot and low power loss. It is consistent with the actual engineering and can be used in most aero-engines. In addition, the entire design methodology is generic and can be transplanted in other actuators design.